Prove of Concept Study, to Evaluate the Efficacy, Safety, and Tolerability of IBEROGAST in the Treatment of Bowel Troubles in Patients With Parkinson's Disease

The main objective of this study is to evaluate the efficacy of STW5 Iberogast, over a 28-day period, for the treatment of constipation in parkinsonian patients suffering from gastrointestinal disorders.

Inclusion Criteria: * Patient 30 to 80 years * Parkinson's disease according to the criteria of the United Kingdom Parkinson's Disease Society Brain Bank * Presence of constipation defined by the Rome III criteria Functional constipation * Social assured Patient * Patients with signed consent Exclusion Criteria: * Organic Affection colic * Constipation Drug * Other neurological disorder Parkinson's disease * Metabolic disease diabetes collagenoses * Severe renal or hepatic impairment * Pregnant or lactating women * Premenopausal women without contraceptive device effective * Regular and prolonged use of history (\> 12 months) of laxatives irritants * Use of oral laxative treatment in the two weeks before the start of treatment, and refusal to stop these treatment during the course of the study * Taking treatment antabuse * Cognitive impairment compromising understanding or application instructions * Patient already included in a research protocol * Minors * Nobody protected by law